Three-dimensional models of large buildings are used in graphical displays to support situation awareness in a variety of situations, such as, for example, firefighting, building security, and HVAC (Heating, Ventilating and Air conditioning) management. In a firefighting scenario, for example, a semitransparent three-dimensional model of a building would be helpful for providing a “birds-eye” perspective view of a building, along with a view from the outside looking in, and with respect to locations of activated smoke and heat detectors in three-dimensional space. From such a display, a firefighter can comprehend the spread of a fire at a glance, particularly the vertical spread between floors or levels of the building. Such a service can provide the firefighter with a very intuitive technique for visualizing a path toward the fire and for viewing the locations of team members.
Users of three-dimensional graphical models of buildings, however, sometimes suffer from disorientation as they view and manipulate three-dimensional building graphics. Without any special aids, all floors of the building tend to look similar. Often floors with special events such as fires, security camera activations, etc. need to be highlighted by shading or other graphical technique so that it is easy for the user to view another part of the building, yet not lose their orientation to the problem floor.
Conversely, a user may desire to “select” a particular floor in the three-dimensional graphics and thereby view the floor in greater detail in contrast to the rest of the building. Common highlighting methods such as shading the flat plane of the selected floor or placing a wireframe around the selected floor can be problematic, particularly if textures are used to render the walls of the building. For example, the floor of a selected floor/level of the building can also be the ceiling of the floor immediately below. Also, it is difficult to present interior details of a particular floor/level such as walls and key objects with the selected floor highlighted, but not clearly separated from the floor above and below it.
In an effort to address the foregoing difficulties, graphical metaphors can be implemented in order to make the selected or highlighted floor and their elements (windows, ceilings, and objects like detectors, etc) absolutely clear and distinct from the floors immediately above and below. An example of such a solution is described in greater detail herein.